Hydrofarm Jump Start Seedling Heat Mat | 9 x 19.5 in, 17W

What a Seedling Heat Mat Changes About Germination

Seeds read soil temperature, not air temperature. A room sitting at 70 F can leave the medium several degrees cooler, and that is where slow, uneven germination comes from. This mat lifts the root zone 10 to 20 F above ambient, and it does that from underneath, where the seed actually is.

Sizing the Hydrofarm Jump Start to Your Bench

This is the narrow one. At 8.875 by 19.5 in it fits a windowsill or the end of a bench rather than a full 10 by 20 flat. That makes it a propagation mat for small runs rather than a tray heater. Power is 17W on 120V through a 6 ft cord, so it draws less than a phone charger across a day. Construction is where the current version differs from older mats. The heating wire is heavier and the multi-layer build is 50% thicker, which spreads heat more evenly and survives a wet bench. It is waterproof and UL listed under registration E325962, with a one year warranty. Light, watering and planting notes are printed on the mat itself, which is more useful than it sounds once the box has gone.

Key Features

• 10 to 20 F over ambient: Heat comes from under the medium, which is where a seed reads temperature.
• 8.875 x 19.5 in: Narrower than a 10 by 20 flat. It suits a windowsill or a bench end.
• 17W on 120V: Less draw than a phone charger across a day, on a 6 ft cord.
• 50% thicker build: A heavier heating wire and multi-layer construction spread heat evenly.
• Waterproof and UL listed: Registration E325962, built for a wet propagation bench.
• Guidance printed on the mat: Light, watering and planting notes stay put once the box is gone.

Technical Specifications